In recent years, national and regional concern about uses of water resources has resulted in concepts of limiting the discharge by domestic appliances, as such discharge is, to a large extent, considered to be waste water. Existing domestic appliances have been designed to discharge water at a much greater rate than is now considered to be desirable.
There already exist flow controllers that, when inserted in flow conduits, respond to pressure and deform in a manner to restrict total flow therethrough. One such controller is disclosed in U.S. Pat. No. 2,728,355.
Ecological and conservation groups have shown increasing interest in urging or requiring employment of controllers for domestic use to prevent using up water resources by discharge through flow appliances at a rate above a predetermined maximum.
It has been observed that use of deformable orifice flow controllers with existing designs of certain domestic appliances, such as showerheads and aerators, tends to develop noise that is objectionable.
It is accordingly one object of the present invention to provide flow limiting flow controllers, of economic design, especially constructed for use with existing domestic flow appliances such as showerheads, aerators, and the like, wherein the controller is adapted for use with existing appliance designs in a manner to avoid development of unwanted noise, and to serve a multiple function of providing an anti-leakage seal for the appliance.
It is another object of the present invention to provide a flow controller for use with flow appliances in which the controller includes an annular upstream support positionable adjacent the central orifice of the flow controlling part for limiting the constriction of that orifice so as to pass only a predetermined maximum volume of fluid per unit time.
Due to the characteristics of the deformable molded material used, and in which the central control orifice is formed, the controllers orifice does not uniformly constrict, but a rotating lobe effect, or precession, occurs. This results in a moving fluid jet, the axis of flow of which describes a generally conical configuration whose apex is at the source of fluid. Because of said conical configuration and velocity, the fluid that issues downstream of the controller does not occupy the full, cross-sectional area available to it, causing some random downstream impingement of the fluid normal, or near normal, to the interior conduit walls. Such action is referred to generally as cavitation, and the impingement is manifested as noise.
It is therefore a further object of the present invention to provide a cavitation noise reducer in the fluid flow path immediately adjacent to and downstream of, the flow controller, the noise reducer in some instances being specifically shaped and designed for cooperation with an existing flow appliance, to reduce the random kinetic flow energy by controlling the direction of travel of the downstream flow.
Further objects and advantages of this invention will become apparent as the following description proceeds, and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed hereto and forming part of this invention.